i think my kids would because i use these places to vent about things they do wrong especially toward me. can't help myself. my parents are gone yrs. ago. i probably would not like it either because my mom always had bad things to say about me even though my aunts and many that knew us did not agree with her treatment of me

Provided you discuss that you would like to blog about your parents, then I think with their approval it would be fine. The same thing with other family members, if discussed, then its okay, given that you respect any requests they may suggest regarding particulars about certain subjects.

I wouldn't mind like @arunima25 if my parents blogged positive things about me. Nothing's worse than seeing negative things about you online. If it was anything embarrassing or negative, then no I would not want my parents to blog about me. So thankfully my parents don't blog. lol